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Flexible spintronic devices based on spin–orbit torque (SOT)-induced perpendicular magnetization switching (PMS) have attracted increasing attention due to their high storage intensity and good programming capability. However, to achieve deterministic PMS, an in-plane auxiliary magnetic field is required, which greatly limits its application. Here, we show that "robust" magnetic field-free SOT-driven PMS is realized in the oblique sputtered Pt/CoTb multilayers grown on a flexible polyimide substrate. "Robust" means the magnetic field-free SOT switching is highly repeatable and stable after 100 bending cycles under various bending conditions. Additionally, the fabricated flexible multilayers exhibit nearly linear and nonvolatile multistate plasticity as synapses and a nonlinear sigmoid activation function when acting as neurons. We construct a fully connected neural network for handwritten digit recognition, achieving an over 96.27% recognition rate. Our findings may spur further investigations on the SOT-based flexible spintronic devices for wearable artificial intelligence applications. [ABSTRACT FROM AUTHOR]

Nonreciprocal magnetotransport is one of the central topics in spintronics because of its importance for electrically probing magnetic information. Among numerous electrical probes used to read magnetic orders, unidirectional magnetoresistance (UMR), characterized by sign changes upon reversal of either current or magnetization, is currently a matter of great interest and has been identified in various spin–orbit-coupled bilayer systems composed of an (anti)ferromagnetic layer and a nonmagnetic layer with strong spin Hall effect. A recent theoretical work predicts that a spin-anomalous-Hall (SAH) UMR in those metallic conducting bilayers can originate from the spin-anomalous-Hall effect of the ferromagnetic layer and the structural inversion asymmetry. However, this type of UMR has not been reported experimentally. Here, we give the experimental evidence of spin-anomalous-Hall UMR in the light-metal/ferromagnetic-metal Cu/Co bilayers, where the emergence of net nonequilibrium spin density is attributed to the interfacial spin leakage asymmetry due to the spin memory loss effect at the Cu/Co interface and multiple spin reflections. We also show a highly tunable UMR in the Cu/Co/CuOx trilayer by varying the Cu thickness, which is due to the competition between the orbital Rashba effect in Co/CuOx and the spin-anomalous-Hall effect in Cu/Co. Our work widens the material choice for UMR device applications and provides an alternative approach to detect in-plane magnetization without an external spin polarizer. [ABSTRACT FROM AUTHOR]

Voltage‐driven oxygen ion migration in ferromagnetic metal/oxide heterostructures offers a highly effective means to tailor emergent interfacial functionalities. In heterojunctions with a core structure of Pt/Co/CoO/TiO2 (TaOx), it is demonstrated that exchange coupling of magnetic moments across the Co/CoO interface provides an extra source to stabilize the perpendicular magnetic anisotropy (PMA). Moreover, the strength of this interfacial coupling can be reversibly controlled through voltage‐driven oxygen ion migration at the Co/CoO interface, resulting in electrical‐field‐controllable PMA. In combination with the spin current generated from Pt, it is revealed that the spin‐orbit torque (SOT) switching of the perpendicular magnetization of Co can be turned ON/OFF by electrical field. Tunable PMA and SOT switching makes heavy metal/ferromagnetic metal/antiferromagnetic oxide heterojunctions a promising candidate to future voltage‐controlled, ultralow‐power, and high‐density spintronics devices. [ABSTRACT FROM AUTHOR]

Emerging nonvolatile multilevel memory devices have been regarded as a promising solution to meet the increasing demand of high‐density memory with low‐power consumption. In particular, decimal system of the new computers instead of binary system could be developed if ten nonvolatile states are realized. Here, a general remanent magnetism engineering method is proposed for realizing multiple reliable magnetic and resistance states, not depending on a specific material or device structure. Especially, as a proof‐of‐concept demonstration, ten states of nonvolatile memory based on the manipulation of ferromagnetic remanent magnetization have been revealed in both Co/Pt magnetic multilayers with strong perpendicular magnetic anisotropy and MgO‐based magnetic tunneling junctions at room temperature. Considering ferromagnets have been one of the key factors that enabled the information revolution from its inception, this state‐of‐the‐art remanent magnetism engineering approach has a very broad application prospect in the field of spintronics. Ten states of nonvolatile memory are demonstrated in both Co/Pt magnetic multilayers and MgO‐based magnetic tunneling junctions based on the manipulation of ferromagnetic remanent magnetization. Moreover, this remanent magnetization engineering method could be adapted to other systems containing multidomain ferromagnets. Hence, this method provides an attractive way toward multilevel nonvolatile memory devices. [ABSTRACT FROM AUTHOR]

Perpendicular magnetization switching by a magnetic-field-free, energy-efficient electrical approach has remained a great challenge. Here, we demonstrate the realization of robust magnetic-field-free perpendicular magnetization switching in the (101)RuO 2 /[Pt/Co/Pt] heterojunction by manipulating the spin polarization direction. We proposed that the relative strength of out-of-plane spin currents with out-of-plane spin polarization σ z and in-plane spin polarization σ y can be effectively manipulated by tuning the nominal thickness of [Pt/Co/Pt] multilayers and the direction of applied electric current with respect to the RuO 2 crystal orientation. When the electric current is applied along RuO 2 [010] direction and the net spin current with spin polarization σ y is canceled out, the "robust" perpendicular magnetization switching driven by pure σ z is achieved in (101)RuO 2 /[Pt/Co/Pt], where the term "robust" means that the switching polarity (counterclockwise) does not change and the switching ratio reduces very slowly with increasing magnitude of in-plane magnetic field H x and/or H y in a wide range of ±500 Oe. Our findings provide a technique to effectively manipulate the spin currents, which is beneficial for the investigation of antiferromagnetic spintronic devices with high magnetic field stability and reliable magnetization switching.

Objective: MicroRNA-23a-3p (miR-23a) is a novel gene regulator involved in inflammation. This study aimed to explore the molecular mechanism of miR-23a in sepsis-induced lung injury both in vitro and in vivo ., Methods: Lipopolysaccharide (LPS)- and ATP-stimulated human myeloid leukemia mononuclear cells (THP-1) and Human Bronchial Epithelial Cells (BEAS-2B) cell lines were used, while cecal ligation and puncture (CLP)-induced sepsis BABL/c mice were constructed. The mRNA expression levels of interleukin (IL)-18, IL-1β, and miR-23a were determined, and Western blotting was used to measure CXCR4/PTEN/PI3K/AKT signaling. The concentrations of cytokines and Nod-like receptor family pyrin domain-containing 3 (NLRP3) were determined using an enzyme-linked immunosorbent assay. Lung tissue of mice was subjected to hematoxylin-eosin staining for examining myocardial injury., Results: MiR-23a inhibited NLRP3 inflammasome activation in LPS- and ATP-stimulated THP-1 and BEAS-2B cells ( P <0.05). Overexpression of miR-23a decreased the lactate dehydrogenase release rate in the cells ( P <0.05). Meanwhile, miR-23a overexpression decreased the concentration and gene expression of IL-1β and IL-18 in CXCR4 positive cells ( P <0.05). Conversely, miR-23a knockdown increased the concentration and gene expression of IL-1β and IL-18 ( P <0.05). Additionally, PTEN and p53 proteins were up-regulated in miR-23a mimic group and down-regulated in miR-23a inhibitor group ( P <0.05). Furthermore, miR-23a expression was decreased in sepsis-induced lung injury mice ( P <0.05). MiR-23a overexpression reduced the sepsis-induced lung injury probably by inhibiting acetylcholinesterase activity and expression levels of IL-1β, IL-18, capase-1, and NLRP3 ( P <0.05)., Conclusion: miR-23a can significantly alleviate sepsis-induced lung injury in CLP-induced septic mice and LPS-stimulated cell lines by suppressing NLRP3 inflammasome activation and inflammatory response, while promoting the CXCR4/PTEN/PI3K/AKT pathway., Competing Interests: None., (AJTR Copyright © 2023.)

The clinical manifestations, types of infectious pathogens, and drug-resistant strains of sepsis in infants with very low birth weight (VLBWIs) vary greatly in different regions and hospitals. In order to improve the level of diagnosis and treatment, this study analyzed the distribution and drug resistance of the pathogenic bacteria of sepsis in VLBWIs in our hospital. A total of 69 cases of VLBWIs in Qilu Hospital (Qingdao), Cheeloo College of Medicine, Shandong University from January 01, 2014 to December 31, 2020 were included. Among them, 34 VLBWIs with early-onset sepsis (EOS) were assigned to the EOS group, and 14 VLBWIs with late-onset sepsis (LOS) were included in the LOS group. The distribution of pathogens and the drug resistance of antibiotics were analyzed. The results showed that fluorescent nanoparticles detected pathogenic bacteria in 48 cases, and the blood cultures were all positive. A total of 49 pathogenic bacteria were isolated, including 27 gram-negative bacteria (55.1%), 21 gram-positive bacteria (42.86%), and 1 fungus (2.04%, Candida albicans). Gram-negative bacteria comprised of E.coli and Klebsiella pneumoniae, which were highly sensitive to compound preparations containing β-lactamase inhibitors, and carbapenem antibacterial drugs, were the first choice. Gram-positive bacteria were mainly Staphylococcus epidermidis and Streptococcus agalactiae. Staphylococcus epidermidis was highly resistant to penicillins and can be treated with vancomycin. Streptococcus agalactiae was highly resistant to penicillins and can be treated with penicillin and vancomycin. Amniotic fluid pollution, intrauterine distress, premature rupture of membranes, and maternal fever were risk factors for EOS in VLBWIs, with odds ratios (ORs) of 9.369, 6.217, 5.638, and 4.267, respectively. In summary, timely and reasonable treatment should be given based on the types and drug resistance characteristics of pathogens of neonatal sepsis and the risk factors of EOS., Competing Interests: None., (AJTR Copyright © 2021.)

Objective: To explore the clinical feature, diagnosis and phenotype of Majeed syndrome., Methods: Clinical manifestation, diagnostic process, imaging feature and genetic testing of an ethnic Han Chinese patient with Majeed syndrome were reviewed., Results: The patient, a 3-year-9-month-old boy, had featured psychomotor retardation and developed bone pain from 8 month on. The child had tenderness of the lower limbs and presented with repeatedly joint swelling and pain accompanied by fever. Physical signs included limb muscle weakening, slightly decreased muscle tone, reduced muscle volume and positive Gower sign. High-throughput sequencing revealed that the child has carried compound heterozygous variants of the LPIN2 gene, including c.1966A>G and c.2534delG. MRI showed multiple lesions in bilateral knee joints and distal middle tibia presenting as patchy SPAIR high signals with unclear edge, in addition with edema of soft tissue surrounding the right distal femur., Conclusion: Majeed syndrome is characterized by chronic and recurrent multifocal osteomyelitis, congenital dyserythropoietic anemia, and growth retardation. Surrounding muscle tissue of osteomyelitis may also be involved. The syndrome may also affect the central nervous system, resulting in delayed language and motor development. Discovery of multiple pathological variants of the LPIN2 gene suggested that the clinical phenotype of this syndrome may vary between patients to some extent.

Objective: To summarize the clinical phenotype and genotype of a Chinese child affected with Mowat-Wilson syndrome (MWS)., Methods: Clinical data of the patient were collected. The patient was analyzed by whole-exome sequencing (WES) as well as Sanger sequencing., Results: The patient was a male infant with recurrent fever and slow growth. He also had characteristic facies, recurrent spasm, and growth retardation. WES revealed that he has carried a heterozygous nonsense c.2609C>G (p.Ser870X) variant of the ZEB2 gene (30% mosaicism). Based on the American College of Medical Genetics and Genomics standards and guidelines, the variant was predicted to be pathogenic (PVS1+PS1+PS2+PM2)., Conclusion: The c.2609C>G variant of the ZEB2 gene probably underlay the MWS in this child. The mosaicism of the variant may explain his mild symptoms.